No, a VPN does not open you to security risks, and in fact offers more security especially when traveling or posting from somewhere like Starbucks. As for slowing your connection down, that's a possibility. That's why you need to review all available options for VPN usage. You may desire to utilize a pay VPN rather than free. There are several real nice pay VPNs which are economical to use and do not interfere with your primary connection.

I am thinking paying for one is the way to go, too. And more security is a plus! I did stumble across the Cloak app a few moments ago, but it seems to be more costly simply because you don't have to configure your settings, like with the other VPN providers.